gemfire::ResultCollector Class Reference

Defines the interface for a container that gathers results from function execution. More...

Inherits gemfire::SharedBase.

Public Member Functions
virtual void	addResult (CacheablePtr &resultOfSingleExecution)
	Adds a single function execution result to the ResultCollector. More...
virtual void	clearResults ()
	GemFire will invoke this method before re-executing function (in case of Function Execution HA) This is to clear the previous execution results from the result collector. More...
virtual void	endResults ()
	GemFire will invoke this method when function execution has completed and all results for the execution have been obtained and added to the ResultCollector}. More...
virtual CacheableVectorPtr	getResult (uint32_t timeout=DEFAULT_QUERY_RESPONSE_TIMEOUT)
	Returns the result of function execution, potentially blocking until all the results are available. More...
void	preserveSB () const
	Atomically increment reference count. More...
int32_t	refCount ()
void	releaseSB () const
	Atomically decrement reference count, the SharedBase object is automatically deleted when its reference count goes to zero. More...
	ResultCollector ()
	public methods More...

Detailed Description

Defines the interface for a container that gathers results from function execution.

GemFire provides a default implementation for ResultCollector. Applications can choose to implement their own custom ResultCollector. A custom ResultCollector facilitates result sorting or aggregation. Aggregation functions like sum, minimum, maximum and average can also be applied to the result using a custom ResultCollector. Example:

 ResultCollectorPtr rc = FunctionService::onRegion(region)
                                     ->withArgs(args)
                                     ->withFilter(keySet)
                                     ->withCollector(new MyCustomResultCollector())
                                     .execute(Function);
 //Application can do something else here before retrieving the result
 CacheableVectorPtr functionResult = rc.getResult();

See also

FunctionService

Constructor & Destructor Documentation

gemfire::ResultCollector::ResultCollector

(

)

public methods

Member Function Documentation

virtual void gemfire::ResultCollector::addResult ( CacheablePtr &  resultOfSingleExecution )

virtual

Adds a single function execution result to the ResultCollector.

Parameters

resultOfSingleExecution

Since

5.8LA

virtual void gemfire::ResultCollector::clearResults ( )

virtual

GemFire will invoke this method before re-executing function (in case of Function Execution HA) This is to clear the previous execution results from the result collector.

Since

6.5

virtual void gemfire::ResultCollector::endResults ( )

virtual

GemFire will invoke this method when function execution has completed and all results for the execution have been obtained and added to the ResultCollector}.

virtual CacheableVectorPtr gemfire::ResultCollector::getResult ( uint32_t  timeout = DEFAULT_QUERY_RESPONSE_TIMEOUT )

virtual

Returns the result of function execution, potentially blocking until all the results are available.

If gemfire sendException is called then ResultCollector.getResult will not throw exception but will have exception UserFunctionExecutionException as a part of results received.

Parameters

timeout

in seconds, if result is not ready within this time, exception will be thrown

Returns

the result

Exceptions

FunctionException

if result retrieval fails

See also

UserFunctionExecutionException

void gemfire::SharedBase::preserveSB ( ) const

inherited

Atomically increment reference count.

int32_t gemfire::SharedBase::refCount ( )

inlineinherited

Returns

the reference count

void gemfire::SharedBase::releaseSB ( ) const

inherited

Atomically decrement reference count, the SharedBase object is automatically deleted when its reference count goes to zero.